Ventriculomegaly

Also known as: hydrocephalus

What is ventriculomegaly?

The ventricles of the brain are a communicating network of cavities (ventricles) deep in the brain consisting of two lateral cavities, a third ventricle, a communicating duct (cerebral aqueduct), and a fourth ventricle, all filled with cerebrospinal fluid (CSF) which is produced by blood vessels (the choroid plexus) in the ventricles.

The brain floats in the CSF fluid surrounding it, and the CSF circulates through the ventricular and the spaces around the brain and the spinal cord, constantly being produced and absorbed.

Ventriculomegaly is a congenital (before birth) condition in which the ventricles of a fetus/baby are abnormally large.

What causes ventriculomegaly?

Large ventricles result from either too little brain tissue surrounding them (because of poor brain development or brain injury) or because there is a block in the ventricular system preventing the CSF from leaving the ventricles or because there is an imbalance between CSF production and absorption (hydrocephalus).

What are the signs/symptoms of ventriculomegaly?

Mild ventriculomegaly may have no signs or symptoms. If however the ventricles are large or increasing in size ( hydrocephalus), a rapidly growing large head, a full or bulging fontanel (soft spot at the top of the head), irritability or sleepiness, poor feeding, abnormal eye movement or always looking downward, projectile vomiting, and developmental delay.

What are ventriculomegaly care options?

Ventriculomegaly may only need to be treated if there is hydrocephalus. Treatment of hydrocephalus usually involves creating a pathway (a shunt) for the excess fluid to flow out of the brain to another area of the body. Endoscopic third ventriculostomy (ETV) creates an opening out of the 3rd ventricle, and a combination of ETV and choroid plexus destruction may be used if other treatments are ineffective.


Reviewed by: Jack Wolfsdorf, MD, FAAP

This page was last updated on: September 09, 2020 10:00 AM

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